Surgical Techniques to Improve Cannulation of Hemodialysis Vascular Access

Transcription

1 Eur J Vasc Endovasc Surg (2010) 39, 333e339 REVIEW Surgical Techniques to Improve Cannulation of Hemodialysis Vascular Access J.H.M. Tordoir a, *, M.M. van Loon a, N. Peppelenbosch a, A.S. Bode a, M. Poeze a, F.M. van der Sande b a Department of Surgery, Maastricht University Medical Center, P Debijelaan 25, 6202 AZ Maastricht, The Netherlands b Department of Nephrology, Maastricht University Medical Center, Maastricht, The Netherlands Submitted 1 September 2009; accepted 26 November 2009 Available online 8 January 2010 KEYWORDS Vascular access; Hemodialysis; Cannulation; Surgical revision Abstract Objective: Successful access cannulation is of utmost importance for adequate hemodialysis treatment. Upper arm fistulae, obesity and deep or tortuous veins may impair needling and can cause significant complications and inconvenience for the patient. In the ultimate case, cannulation problems lead to temporary central vein catheter use for dialysis or even to irreversible access loss. Surgical access revision may enhance successful cannulation. Methods: A systematic literature review of all publications related to hemodialysis vascular access, cannulation complications and treatment was performed. Results: A total of 384 publications were identified, of which only 17 were related to treatment of cannulation complications in large patient populations. The clinical success rate of surgical intervention with vein elevation or transposition ranges from 85% to 91%. The 1-year primary and secondary patencies are 60% and 71%, respectively. Lipectomy results in an initial success rate of 100% with a primary and secondary patency of 71% and 98%, respectively, after 1 year of follow-up. Conclusion: Surgical revision to improve hemodialysis vascular access cannulation has a high clinical success rate with good long-term patency. ª 2009 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. Introduction Miscannulation of hemodialysis vascular access may cause infiltrations, haematoma formation, infection and aneurysms, and leads to morbidity, hospitalisation, access * Corresponding author. Tel.: þ ; fax: þ address: j.tordoir@mumc.nl (J.H.M. Tordoir). revision and even loss of the access. Difficult cannulation is painful and burdensome for the patient, which has a negative impact on the quality of life. Recent studies have shown cannulation-related complications in a great percentage (31%) of incident patients. In addition, alternative access methods, such as single-needle cannulation and central vein catheters were needed in these patients, with a potential higher morbidity and mortality rate. Miscannulation and cannulation-related complications are /$36 ª 2009 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. doi: /j.ejvs

2 334 J.H.M. Tordoir et al. usually seen in autogenous arteriovenous fistulae (AVFs) but also occur in AV grafts. Obesity, female sex and the length of the cannulation route are important factors for the occurrence of cannulation-related complications. In a univariate analysis of patients with AVF, female sex (P < 0.02) and limited length of cannulation route (P < 0.003) were significant determinants for the use of catheter or single-needle dialysis. Multivariate analysis showed the limited length of cannulation route as the single predictive factor for cannulation problems (P < 0.002). Upper arm AVF exhibit more cannulation problems than forearm fistulae, but the difference is not statistically significant. 1 Ultrasound-guided needling may facilitate successful cannulation of difficult access, but this technique can be cumbersome to learn by dialysis nurses and extended experience is needed for good outcome. Surgical access revision may enhance access cannulation and improve fistula outcome. For the description and outcome of the various surgical techniques, a literature review was performed. Methods A systematic literature review using a Medline search of English-language publications was performed. Keywords used were: vascular access; hemodialysis; cannulation; complications. For this review in particular, large population-based, randomised studies and meta-analysis were included. Small patient studies and case reports were excluded. A total of 384 studies were identified; 367 studies were excluded for review because of: not meeting the inclusion criteria (n Z 214); case reports (n Z 106) and non- English-language publications (n Z 47). None of the identified studies was randomised or concerned a meta-analysis. Seventeen studies were eligible for review, including various techniques to enhance access cannulation. A test of heterogeneity showed no significant deviation of the different papers from the normal distribution. Aetiology of miscannulation Non-maturation Fistula cannulation can be usually performed after successful maturation. A time period of 6 weeks to 3 months is sufficient to achieve adequate maturation in most patients. According to the National Kidney FoundationeKidney Diseases Outcome Quality Initiative (NKFeKDOQI) guidelines autogenous fistulae have matured when they fulfil three criteria: a vein diameter of 6 mm; a blood flow of 600 ml min 1 and a vein depth of less than 6 mm. 2 These criteria are hardly met with in daily practice. As much as 30e40% of radiocephalic wrist fistulae and 10e20% of elbow and upper arm fistulae (brachiocephalic/basilic) fail or do not mature after creation. The reason for non-maturation is, in 90% of patients, a stenotic lesion at the arteriovenous anastomosis or arterial inflow. In addition, large-calibre accessory veins may be associated with non-maturation and cannulation difficulties. In 10 out of 15 patients with radiocephalic arteriovenous fistulae (RCAVFs), the presence of large-calibre accessory veins was the only significant predictor for non-maturation (P Z 0.01). 3 Obesity and deeply located veins The number of obese end-stage renal disease patients, who frequently have type 2 diabetes, is continuously increasing. On the one hand, obese and diabetic patients belong to a group with an increased risk of autogenous arteriovenous fistula placement failure due to advanced arteriosclerosis and reduced accessibility of forearm vessels because of excessive fat tissue. Moreover, needling of the deeply located veins may be difficult. Up to 50% of AVFs may fail to mature, primarily because of problems with fistula cannulation. On the other hand, while physical examination usually does not show superficial veins in these patients, Doppler ultrasound vessel imaging may identify well-sized, good-quality radial arteries and cephalic veins for fistula creation and these are comparable between obese and non-obese patients. 4 Still, AVF use for dialysis is less frequent among obese than non-obese patients. This discrepancy may be due to a lower rate of fistula placement in obese patients and a higher primary and secondary failure rate. A prospective study showed that fistula placement was equally likely between obese (body mass index (BMI) 30 kg m 2 ) and non-obese (BMI <30 kg m 2 ) patients (47.4 vs. 47.1%). The primary failure rate of fistulae was similar in both groups (46 vs. 41%, P Z 0.45). Among those fistulae that were usable for dialysis, the secondary survival was worse in obese patients (hazard ratio 2.74; 95% confidence interval (CI), 1.48e7.90; P Z 0.004). Secondary fistula survival in obese versus nonobese patients was 68% versus 92% at 1 year, 59% versus 78% at 2 years and 47% versus 70% at 3 years. On multivariate survival analysis with age, sex, race, diabetes, coronary artery disease, peripheral vascular disease, fistula location, surgeon and obesity in the model, obesity was the only significant factor predicting secondary fistula failure (hazards ratio 2.93; 95% CI, 1.44e5.93; P Z 0.004). Longterm fistula survival is worse in obese than non-obese patients, owing to a higher secondary failure rate. Access failure in obese patients may be due to needling difficulties resulting in cannulation-related complications. 5 In a large retrospective study, 1486 hemodialysis patients were included. Using BMI <30 kg m 2 as reference, obesity did not emerge as a factor in predicting vascular access revisions or failures. An increased risk of AVF failure to mature was found only in the highest BMI quartile (>35 kg m 2 )(Adjusted odds ratio (AOR) 3.66 (95% confidence interval (CI): 1.27e 10.55), P Z 0.017). Peripheral vascular disease was independently associated with an increased risk of AVF failure (AOR 2.78 (95% CI 1.01e7.63), P Z 0.047) and arteriovenous graft (AVG) failure (AOR 1.65 (95% CI 1.03e2.64), P Z 0.036). Obesity was not associated with increased AVF or AVG revision rates or failure and only associated with poorer AVF maturity at the highest BMI quartile. 6 Short vein segment and/or tortuosity Vein anatomy may differ widely among patients, which implies a variety of accessible vein segments after access creation. In some patients, meandering veins may lead to

3 Vascular Access Revision 335 difficult (mis)cannulation with greater chance of haematoma. Radio/brachiocephalic fistulae may develop stenosis and subsequently obstruction at the site of side branches. Usually, a short vein segment remains available for cannulation. However, this segment may be unsuitable for two-needle dialysis. Further, short vein segments result in a higher percentage of miscannulation and complications. 7 Surgical techniques to enhance cannulation Vein elevation and transposition If the flow and size of the fistula are adequate, subcutaneous elevation or transposition is an ideal procedure. The vein can be directly superficialised under the wound (Fig. 1(A)e(C)), or tunnelled to a more favourable location for needling, if required. It is important to avoid placing the vein under tension and disconnection with re-formation of the anastomosis may be required. The fistula elevation procedure (FEP) is a simple superficialisation procedure where the fistula is surgically exposed, mobilised and elevated into a more superficial position for the purpose of facilitating AVF cannulation. The FEP procedure can be performed in a one or two-staged operation (second operation between 4 and 9 weeks after fistula creation to allow for vein maturation). A longitudinal incision is made some distance away from the fistula vein, running from the wrist to the proximal forearm in the patients with an RCAVF and from the antecubital fossa to the proximal upper arm in patients with a brachiocephalic arteriovenous fistula (BCAVF). The fistula is mobilised along the length of the incision. It is important to be aware that skin incision directly over the vein may result in excessive scar tissue, which hampers future access needling. Tributaries are ligated with fine silk sutures and divided. The subcutaneous fat is than approximated beneath the fistula with interrupted 3/0 Vicryl suture, thereby elevating the fistula to a superficial position. The skin is closed over the fistula with a running subcuticular 4/0 Vicryl suture. 8e10 Silva et al. 11 have described a high maturation and cannulation rate with subcutaneous elevation and transposition of forearm veins in an one-stage operation. They advocated different surgical techniques, according to the forearm artery and vein location. Of the 89 veins that were of acceptable size and patency, 13 (15%) were in immediate proximity to the radial artery such that an AVF could be formed through a single incision. Thirty of 89 (33%) of the veins were located on the dorsal aspect of the forearm and were transposed to the volar aspect for anastomosis to the appropriate artery (radial in 26, ulnar in two and brachial in two). The remaining 46 of 89 veins (52%) were located on the volar aspect of the forearm but were dissected through separate incisions, transposed superficially and sutured to the appropriate artery (radial in 42, ulnar in two and brachial in two). Successful cannulation and hemodialysis was accomplished in 81 of the 89 AVFs, giving a maturation rate of 91%. Primary patency rates were 84% at 1 year and 69% at 2 years for all AVFs. The two-staged FEP technique has been performed by Weyde et.al. 12 in 71 obese patients with RCAVFs. In the first stage, an autogenous AVF was created in the wrist region. In the second stage, which was carried out 10e14 days after fistula formation, an arterialised vein was elevated subcutaneously to enable safe needling. The time span between the two procedures allowed for saving of the vein for a second, more proximal anastomosis in the event of initial fistula failure. Sixty-five patients with functioning fistulae underwent the second-stage operation, which was successful in 60 patients (85%). The cause of unsuccessful elevation in four patients was insufficient blood flow through the vein. In one patient, the vein elevation produced a large haematoma that resulted in fistula thrombosis. Primary patency rates were 65% at 6 months and 59% at 1 year. Secondary patency rates were 83% at 6 months and remained steady after a 1-year observation (Fig. 2(A) and (B)). The largest series of fistula elevation procedures comprise 295 patients (172 brachiocephalic, 70 brachiobasilic, 46 radiocephalic and 7 superficial femoral vein). FEP was performed if the fistula was considered too deep to cannulate or if nurses were unable to cannulate the fistula. Functional primary patency rates for patients undergoing an adjunctive FEP were 73% at 6 months, 60% at 1 year and 46% at 2 years. Secondary functional patency rates were 81% at 6 months, 71% at 1 year and 59% at 2 years. There was no statistical significance in any outcomes based on anatomic site of elevation. 13 An alternative technique is subcutaneous transposition of the cephalic vein in the fore- or upper arm, which is done in a two-staged operation. This technique is also possible for a deeply located non-transposed basilic vein after the creation of a brachiocubital (Gracz) fistula. After vein dissection and transsection 2 cm proximal of the AV anastomosis, subcutaneous rerouting of the vein with a tunneller along a straight course is performed with subsequent re-anastomosis to the vein stump near to the already existing AV anastomosis. AV fistulae that might otherwise have been abandoned because of excessive depth or tortuosity can be successfully salvaged by an adjunctive elevation or transposition procedure and achieve satisfactory long-term functional patency. Vein stretching and accessory vein ligation Large (>50% of main vein diameter) accessory veins may divert flow from the main vein, making needling more challenging. These tributaries can be ligated under local anaesthesia, through small stab incisions adjacent to the vein. It is best to place the incision a little way from the branch point to avoid ligating or damaging the main vein. A vein hook, as used for phlebectomy, can be used to gently hook up smaller veins and ligate them. This is a straightforward procedure, usually made more accurate by preoperative duplex mapping. Beathard et al. 14 have published on the treatment of fistula non-maturation, including accessory vein ligation. A total of 100 patients who met the definition of early failure were identified. Arterial, juxta-anastomotic, venous or a combination of stenotic lesions was present in almost all patients. Accessory veins were present in 46% and in 12% this was the only lesion present. Angioplasty was performed

4 336 J.H.M. Tordoir et al. Figure 1 AeC. Schematic drawing of the elevation technique. to treat venous stenosis in 72% of the cases with a 98% success rate. Angioplasty of the arterial anastomosis was performed in 38 cases with a 100% success rate. Accessory vein obliteration was performed in 46% of the patients with a 100% success rate. It was possible to initiate dialysis using the fistula in 92% of the cases. Life-table analysis showed that 84% were functional at 3 months, 72% at 6 months and 68% at 12 months. Usually, salvage procedures with endovascular (PTA or percutaneous transluminal angioplasty) and/or surgical procedures result in a high success percentage resulting in blood flow enhancement, vessel adaptation and dilatation and secondary maturation and cannulation. 15 The surgical technique of vein stretching is similar to vein transposition. The tortuous vein is dissected and side branches ligated. The vein is transsected near the AV anastomosis. The excess vein length is trimmed and after subcutaneous rerouting, a re-anastomosis to the venous stump with 6/0 polypropylene suture (Prolene â ) is performed. Wound healing with vein ingrowth in the subcutaneous tunnel for a period of 4e6 weeks is obligatory, before any needling is started. Local vein revision Segmental vein stenosis and/or aneurysm may impair cannulation and can be revised by endovascular or surgical means. PTA is the first treatment option for segmental stenoses. As an alternative, vein or graft interposition/ patch can augment the area of needling sites.

5 Vascular Access Revision 337 Figure 2 A. Results of two-stage elevation technique. Primary patency rates are 65% (SE 0.056), 59% (SE 0.059), 53% (SE 0.061) and 33% (SE 0.065) at 6, 12, 24, 36 months, respectively (SE Z standard error). The numbers above the curve represent numbers at risk (reproduced from Weyde et al. 12 with permission). B. Results of two-stage elevation technique. Secondary patency rates are 83% (SE 0.04), 83% (SE 0.04), 80% (SE 0.05) and 68% (SE 0.06) at 6, 12, 24, 36 months, respectively (SE Z standard error) (reproduced from Weyde et al. 12 with permission). Lipectomy An alternative technique is lipectomy with removal of the subcutaneous fat between the vein and the skin. 16 Two transverse skin incisions are made over the cephalic vein, 8 cm apart. The fat is removed over a length of approximately 4 cm on each side of each incision. The dissection is facilitated by elevation of the skin with hooks. The periadventitial plane is opened and dissected between the fascia superficialis and the anterior surface of the vein. The use of a tourniquet allows for easy bloodless separation of the vein and the fascia. The posterior part of the subcutaneous fatty tissue is dissected medially from the anterior surface of the vein and cut laterally. The anterior part of the subcutaneous fatty tissue is bluntly separated from the skin, with the exception of the most superficial part (1 mm deep). This approximately 4-cm-long dissection is performed distally and proximally from each incision site. The tissues were cut medially and laterally 2 cm from the vein. The fat pad and the underlying fascia are then excised. In a single-centre prospective study, 49 consecutive patients underwent lipectomy after creation of

6 338 J.H.M. Tordoir et al. Figure 3 Results of lipectomy. Primary patency rates (solid line) are 71% (SE 0.07), 67% (SE 0.07) and 63% (SE 0.08) at 12, 24 and 36 months, respectively. Secondary patency rates (dashed line), are 98% (SE 0.02), 94% (SE 0.04), and 88% (SE 0.07) at 12, 24 and 36 months respectively (SE Z standard error). The numbers at the bottom of the graph represent numbers at risk (reproduced from Bourquelot et al. 17 with permission). a radiocephalic fistula. The mean BMI was kg m 2. Subcutaneous fatty tissues were removed with two transverse skin incisions under regional anaesthesia and preventive haemostasis. Cannulation was first allowed 1 month later, after clinical and colour duplex ultrasound evaluation. Technical success was defined as the ability to remove the fat and to palpate the patent vein immediately under the skin at the end of the operation. Clinical success was defined as the ability to perform at least three consecutive dialysis sessions with two needles. Technical and clinical success rates were 96% and 94%, respectively. Mean vein depth decreased from 8 2 to 3 1 mm according to duplex ultrasound imaging. The mean vein diameter increased from 6 1 mm to 8 2 mm. In one patient, vein tortuosity that was overlooked required conventional repeat tunnelling. One extensive haematoma resulted in loss of the fistula. One patient died before the fistula could be used. Primary patency rates were 71% and 63% at 1 and 3 years, respectively, and secondary patency rates were 98% and 88% (Fig. 3). Complications were treated by surgery (7) or by endovascular procedures (10). 17 Discussion Cannulation difficulties and complications appear in onethird of patients with autogenous and graft AVFs. In particular, obese patients and patients with upper arm fistulae are at risk for miscannulation. Cannulation problems result in local infiltration, infection and aneurysmatic vein dilatation, which urge the physician to shift to central vein catheter dialysis or even abandonment of the access. Adjustment of the cannulation practice, for instance, adding sonography to guide needling of deeply located veins or changing cannulation technique (buttonhole), may help some patients to overcome difficult cannulation. However, in a great number of patients, these changes in practice patterns do not result in a better outcome. Endovascular and/or surgical interventions are therefore helpful to treat cannulation-related complications. Nonmatured or stenosed veins are treated by endovascular means as a primary option. Surgical techniques, employing vein elevation/stretching/transposition and repositioning are indicated, in particular, in deeply located or tortuous veins. Alternative techniques such as lipectomy are useful to solve cannulation inability in obese patients. In the literature, only scarce information on the outcome of surgical revisions has been referenced. However, they show a high primary success rate and good long-term patencies and amongst the different methods of vein superficialisation or lipectomy, the outcomes are comparable. In conclusion, surgical intervention is useful to enhance cannulation practice in obese patients and difficult accesses. Nephrologists and vascular surgeons should be aware of the possibilities of surgical interventions and may offer these to their dialysis patients with persistent cannulation difficulties and complications. Conflict of interest/funding None. References 1 van Loon MM, Kessel AG, van der Sande FM, Tordoir JH. Cannulation practice patterns in hemodialysis vascular access: predictors for unsuccessful cannulation. J Ren Care 2009;35(2):82e9. 2 NKF-KDOQI. Clinical practice guidelines and clinical practice recommendations for vascular access: update Am J Kidney Dis 2006;48(Suppl. 1):S176eS Planken RN, Duijm LE, Kessels AG, Leiner T, Kooman JP, van der Sande FM, et al. Accessory veins and radialecephalic

7 Vascular Access Revision 339 arteriovenous fistula non-maturation: a prospective analysis using contrast-enhanced magnetic resonance angiography. J Vasc Access 2007;8:281e6. 4 Vassalotti JA, Falk A, Cohl ED, Uribarri J, Teodorescu V. Obese and non-obese hemodialysis patients have a similar prevalence of functioning arteriovenous fistula using pre-operative vein mapping. Clin Nephrol 2002;58(3):211e4. 5 Kats M, Hawxby AM, Barker J, Allon M. Impact of obesity on arteriovenous fistula outcomes in dialysis patients. Kidney Int 2007;71:38e43. 6 Chan MR, Young HN, Becker YT, Yevzlin AS. Obesity as a predictor of vascular access outcomes: analysis of the USRDS DMMS wave II study. Semin Dial 2008;21(3):274e9. 7 van Loon MM, Kessels AGH, van der Sande FM, Tordoir JHM. Cannulation and vascular access-related complications in hemodialysis: factors determining successful cannulation. Hemodial Int 2009;13:498e Cull DL, Taylor SM, Carsten CG, Youkey JR, Snyder BA, Sullivan TM, et al. The fistula elevation procedure: a valuable technique for maximizing arteriovenous fistula utilization. Ann Vasc Surg 2002;16(1):84e8. 9 Weyde W, Krajewska M, Letachowicz W, Klinger M. Superficialization of the wrist native arteriovenous fistula for effective hemodialysis vascular access construction. Kidney Int 2002; 61(3):1170e3. 10 Arenas MD, Gil MT, Malek T, Moledous A, Nuñez C, López- Collado M. Superficialization of autologous vascular access: an alternative to the use of vascular prostheses and permanent catheters. Nefrologia 2009;29(1):67e Silva MB, Hobson RW, Pappas PJ, Haser PB, Araki CT, Goldberg MC, et al. Vein transposition in the forearm for autogenous hemodialysis access. J Vasc Surg 1997;26:981e8. 12 Weyde W, Krajewska M, Letachowicz W, Porazko T, Watorek E, Kusztal M, et al. Obesity is not an obstacle for successful autogenous arteriovenous fistula creation in hemodialysis. Nephrol Dial Transplant 2008;23(4):1318e Bronder CM, Cull DL, Kuper SG, Carsten CG, Kalbaugh CA, Cass A, et al. Fistula elevation procedure: experience with 295 consecutive cases during a 7-year period. J Am Coll Surg 2008; 206(5):1076e Beathard GA, Arnold P, Jackson J, Litchfield T. Physician operators forum of RMS lifeline. Aggressive treatment of early fistula failure. Kidney Int 2003;64(4):1487e Voormolen EH, Jahrome AK, Bartels LW, Moll FL, Mali WP, Blankestijn PJ. Nonmaturation of arm arteriovenous fistulas for hemodialysis access: a systematic review of risk factors and results of early treatment. J Vasc Surg 2009;49(5):1325e Roberts C. Saving a brachiocephalic fistula using lipectomy. Nephrol Nurs J 2005;32(3): Bourquelot P, Tawakol JB, Gaudric J, Natario A, Franco G, Turmel-Rodrigues L, et al. Lipectomy as a new approach to secondary procedure superficialization of direct autogenous forearm radialecephalic arteriovenous accesses for hemodialysis. J Vasc Surg 2009 Aug;50(2):369e74.